fix(draw-route): fix typo for "add assumptions"

Fixes #68

Author: Glavin001

app/views/draw.html

@@ -242,7 +242,7 @@
                 <button class="btn btn-primary form-control"
                 ng-click="model.addAssumption()">
                     <span class="glyphicon glyphicon-plus"></span>
-                    Add Asssumption
+                    Add Assumption
                 </button>
             </div>